This invention relates in general to vehicle engines and in particular to an improved composite intake manifold assembly for use in such a vehicle engine and method for producing the same.
An intake manifold assembly of a multi-cylinder engine includes a plurality of branched air passageways or ducts. Each of the air passageways defines a generally tubular runner having an air intake port and an opposite air inlet port. The air intake port of the runner is connected to an associated plenum which supplies atmospheric, turbo, or supercharged air to the runner intake port, and the air inlet port is connected to a flange which is connected to an associated inlet port of each cylinder head of the engine to supply the air from the runner to each cylinder head. Conventional intake manifold assemblies are constructed of cast iron, magnesium, aluminum, and plastic.
A typical aluminum intake manifold assembly is produced entirely by conventional casting process. These manifolds typically include a plurality of tubes disposed having first ends connected with the outlet holes of an air intake plenum, and second opposite ends connected with the associated holes of a flange member which is adapted for mounting to a cylinder head of the engine. Since the tubes are usually U-shaped, the manifold cannot be cast in one piece but rather must be cast in two sections, with one section comprising a length of the tubing cast integrally with the plenum and the other section comprising the remaining length of the tubing cast integrally with the flange member. The halves must then be joined together with bolts and a gasket or other suitable hardware to complete the manifold, further adding to the cost and complexity of the manifold.
A typical plastic multi-piece manifold assembly includes an upper half shell and a lower half shell which are joined together by a welding process. In some instances the plastic multi-piece manifold assembly includes one or more inner shell pieces which are disposed within the upper and/or lower half shells. The inner shell can be lower partial inserts which are secured to lower half shell; upper partial inserts which are secured to the upper half shell, or both lower and upper partial inserts which are secured to the respective lower and upper half shells. The inserts are typically joined to the associated half shell by a conventional heat staking process or welding process. In some instances, a plurality of individual blow molded tubes are disposed within the upper and lower half shells and joined thereto by a conventional heat staking process. In both types of constructions, the inserts or the inserts in cooperation with upper or lower half shells define a corresponding number of runner paths through which air is supplied to the associated cylinder head of the engine.
This invention relates to an improved composite air intake manifold assembly adapted for use with an internal combustion engine and method for producing the same. The composite air intake manifold assembly includes an upper half shell formed from a polymer, a lower half shell formed from a polymer and joined to the upper half shell to define a housing having an internal cavity, and a one piece inner shell formed from a polymer and disposed within the cavity. The one piece inner shell in combination with the upper half shell and the lower half shell cooperate to define at least a pair of spaced apart air intake runners. Each of the runners includes an opened air intake end adapted to receive atmospheric air, and an opened air inlet end adapted to be connected to an associated air inlet side of a cylinder head of the internal combustion engine. The method for producing the composite air intake manifold assembly includes the steps of: (a) providing an upper half shell formed from a polymer; (b) providing a lower half shell formed from a polymer; (c) providing a one piece inner shell formed from a polymer; (d) disposing the one piece inner shell in one of the lower half shell and the upper half shell; (e) subsequent to step (d), joining the one piece inner shell to the one of the lower half shell and the upper half shell; and (f) joining the one piece inner shell to the other one of the lower half shell and the upper half shell to thereby produce the composite air intake manifold assembly, wherein the one piece inner shell in combination with the upper half shell and the lower half shell cooperate to define at least a pair of spaced apart air intake runners, each of the runners including an opened air intake end, adapted to receive atmospheric air, and an opened air inlet end, adapted to be connected to an associated air inlet side of a cylinder head of the internal combustion engine. The one piece inner shell of the air intake manifold assembly of this invention can be formed for a variety of different vehicle engine applications. As a result of this, various runner lengths and plenum volumes of the air intake manifold assembly can be attained by only modifying the one piece inner shell of the present invention.
Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.